Assistant House Minority Leader James E. Clyburn of South Carolina threw cold water on a push from the Congressional Black Caucus to have President Barack Obama nominate him to be Transportation secretary.

“He’s proud and honored that some of his colleagues think enough of him to recommend him for Transportation secretary, but the only job change Mr. Clyburn is working on is once again becoming majority whip when the American people reject the Republicans’ failed leadership and extreme partisan gamesmanship and Democrats win back the House,” said Clyburn spokesman Patrick Devlin.

As National Journal first reported, CBC Chairwoman Marcia L. Fudge, D-Ohio, sent a letter to Obama urging him to name Clyburn, the highest-ranking and longest-serving African-American in Congress, to the post after current secretary Ray LaHood announced his retirement last week.

The letter on behalf of Clyburn is part of a larger effort to encourage more diversity in Obama’s second administration, something that has been highlighted as an issue by outside groups. Over the past few weeks, Fudge has also sent letters to Obama suggesting that he appoint CBC members Barbara Lee, D-Calif., to be Labor secretary and Melvin Watt, D-N.C., to be Commerce secretary.

“The CBC is very concerned about the diversity of the president’s Cabinet and they are making a concerted push to put forward qualified candidates,” a former Democratic leadership aide said.

A CBC spokeswoman, however, downplayed the notion that Fudge was trying to nudge Obama into appointing more African-Americans, stating that while Fudge does believe diversity to be important, that is not her primary motivation.

“Ms. Fudge and other members of the CBC believe that diversity in the Cabinet is important and members of the CBC are qualified for the position,” said CBC spokeswoman Ayofemi Kirby. “She just believes that Mr. Watt, Ms. Lee and Mr. Clyburn should be considered for the position.”

Inter-chamber rivalry may also be at play, said former CBC Executive Director Paul Brathwaite. LaHood, former White House Chief of Staff Rahm Emanuel and outgoing Labor Secretary Hilda E. Solis were once House members, but their departure leaves a lack of ex-congressmen in the White House, just as Obama appoints several former senators.

“What the members are saying is it would be nice to have a colleague from the House in the cabinet after Secretary Solis’ departure,” Brathwaite said. “If there’s going to be a concerted effort to do big things in Congress and big things as an executive and legislative branch working together, obviously having people who know and understand the institution would be to the president’s advantage.”